[#186] fix: wire --config through dispatch path for update and install

apps/pair-cli/src/cli.ts

@@ -191,10 +191,12 @@ function registerCommandFromMetadata(
     const config = cmdConfig.parse(normalizedOptions, positionalArgs)
 
     const initCwd = process.env['INIT_CWD']
+    const configPath = normalizedOptions['config'] as string | undefined
     await dispatchCommand(config, fsService, {
       httpClient,
       cliVersion: version,
       ...(initCwd && { baseTarget: initCwd }),
+      ...(configPath && { config: configPath }),
     })
   })
 }

apps/pair-cli/src/commands/dispatcher.test.ts

@@ -11,6 +11,84 @@ import type {
 } from './index'
 import type { KbInfoCommandConfig } from './kb-info/parser'
 
+/**
+ * #186: config forwarding from dispatch context to handlers
+ *
+ * Verifies that the dispatcher forwards the `config` field from the
+ * dispatch context to handler options for both update and install commands.
+ */
+describe('#186 — config forwarding through dispatch context', () => {
+  let fs: InMemoryFileSystemService
+  const cwd = '/project'
+
+  beforeEach(() => {
+    fs = createTestFs(
+      {
+        asset_registries: {
+          reg: {
+            source: 'reg',
+            behavior: 'mirror',
+            targets: [{ path: 'dest', mode: 'canonical' }],
+            description: 'base target',
+          },
+        },
+      },
+      {
+        [`${cwd}/package.json`]: JSON.stringify({ name: 'test', version: '0.1.0' }),
+        [`${cwd}/packages/knowledge-hub/package.json`]: JSON.stringify({
+          name: '@pair/knowledge-hub',
+        }),
+        [`${cwd}/packages/knowledge-hub/dataset/reg/file.txt`]: 'content',
+        // Custom config overrides target path
+        [`${cwd}/custom.json`]: JSON.stringify({
+          asset_registries: {
+            reg: {
+              source: 'reg',
+              behavior: 'mirror',
+              targets: [{ path: 'custom-dest', mode: 'canonical' }],
+              description: 'custom target',
+            },
+          },
+        }),
+      },
+      cwd,
+    )
+    vi.restoreAllMocks()
+  })
+
+  test('forwards config to update handler — output uses custom registry target', async () => {
+    // Pre-existing targets (update precondition)
+    await fs.mkdir(`${cwd}/dest`, { recursive: true })
+    await fs.writeFile(`${cwd}/dest/file.txt`, 'old')
+    await fs.mkdir(`${cwd}/custom-dest`, { recursive: true })
+    await fs.writeFile(`${cwd}/custom-dest/file.txt`, 'old')
+
+    const config: UpdateCommandConfig = {
+      command: 'update',
+      resolution: 'default',
+      kb: true,
+      offline: false,
+    }
+
+    await dispatchCommand(config, fs, { config: `${cwd}/custom.json` })
+
+    expect(await fs.readFile(`${cwd}/custom-dest/file.txt`)).toBe('content')
+  })
+
+  test('forwards config to install handler — output uses custom registry target', async () => {
+    const config: InstallCommandConfig = {
+      command: 'install',
+      resolution: 'default',
+      kb: true,
+      offline: false,
+    }
+
+    await dispatchCommand(config, fs, { config: `${cwd}/custom.json` })
+
+    expect(await fs.exists(`${cwd}/custom-dest/file.txt`)).toBe(true)
+  })
+})
+
 describe('dispatchCommand() - real handlers integration', () => {
   let fs: InMemoryFileSystemService
   const cwd = '/project'

apps/pair-cli/src/commands/dispatcher.ts

@@ -6,6 +6,7 @@ interface DispatchContext {
   httpClient?: HttpClientService
   cliVersion?: string
   baseTarget?: string
+  config?: string
 }
 
 async function dispatchWithExitCode(handler: () => Promise<number>): Promise<void> {
@@ -50,5 +51,6 @@ function resolveOptions(ctx: DispatchContext) {
     ...(ctx.httpClient && { httpClient: ctx.httpClient }),
     ...(ctx.cliVersion && { cliVersion: ctx.cliVersion }),
     ...(ctx.baseTarget && { baseTarget: ctx.baseTarget }),
+    ...(ctx.config && { config: ctx.config }),
   }
 }

apps/pair-cli/src/commands/install/handler.test.ts

@@ -4,6 +4,99 @@ import type { InstallCommandConfig } from './parser'
 import { createTestFs } from '#test-utils'
 import { InMemoryFileSystemService } from '@pair/content-ops'
 
+/**
+ * #186: config override via options.config
+ *
+ * Verifies that handleInstallCommand uses a custom config when
+ * options.config is provided, and falls back to base config otherwise.
+ */
+describe('#186: config override via options.config', () => {
+  const cwd = '/test-project'
+  const datasetSrc = `${cwd}/packages/knowledge-hub/dataset`
+
+  let fs: ReturnType<typeof createTestFs>
+
+  beforeEach(() => {
+    fs = createTestFs(
+      {
+        asset_registries: {
+          github: {
+            source: 'github',
+            behavior: 'mirror',
+            targets: [{ path: '.github', mode: 'canonical' }],
+            description: 'GitHub registry',
+          },
+        },
+      },
+      {
+        [`${cwd}/package.json`]: JSON.stringify({ name: 'test-pkg', version: '0.1.0' }),
+        [`${cwd}/packages/knowledge-hub/package.json`]: JSON.stringify({
+          name: '@pair/knowledge-hub',
+        }),
+        [`${datasetSrc}/github/workflow.yml`]: 'content: val',
+        [`${datasetSrc}/custom-reg/data.md`]: '# Custom Install Data',
+      },
+      cwd,
+    )
+  })
+
+  test('uses custom config registries when options.config is provided', async () => {
+    const customConfig = {
+      asset_registries: {
+        'custom-reg': {
+          source: 'custom-reg',
+          behavior: 'mirror',
+          targets: [{ path: '.custom-target', mode: 'canonical' }],
+          description: 'Custom registry',
+        },
+      },
+    }
+    await fs.writeFile(`${cwd}/custom-config.json`, JSON.stringify(customConfig))
+
+    const config: InstallCommandConfig = {
+      command: 'install',
+      resolution: 'default',
+      kb: true,
+      offline: false,
+    }
+
+    await handleInstallCommand(config, fs, {
+      config: `${cwd}/custom-config.json`,
+    })
+
+    expect(await fs.exists(`${cwd}/.custom-target/data.md`)).toBe(true)
+    expect(await fs.readFile(`${cwd}/.custom-target/data.md`)).toBe('# Custom Install Data')
+  })
+
+  test('uses base config when options.config is not provided', async () => {
+    const config: InstallCommandConfig = {
+      command: 'install',
+      resolution: 'default',
+      kb: true,
+      offline: false,
+    }
+
+    await handleInstallCommand(config, fs)
+
+    expect(await fs.exists(`${cwd}/.github/workflow.yml`)).toBe(true)
+  })
+
+  test('throws when options.config points to non-existent file', async () => {
+    const config: InstallCommandConfig = {
+      command: 'install',
+      resolution: 'default',
+      kb: true,
+      offline: false,
+    }
+
+    await expect(
+      handleInstallCommand(config, fs, {
+        config: `${cwd}/nonexistent.json`,
+      }),
+    ).rejects.toThrow(/Failed to load custom config/)
+  })
+})
+
 describe('handleInstallCommand - real services integration', () => {
   const cwd = '/test-project'
 

apps/pair-cli/src/commands/install/parser.ts

@@ -76,6 +76,7 @@ interface ParseInstallOptions {
   kb?: boolean
   skipVerify?: boolean
   listTargets?: boolean
+  config?: string
 }
 
 function buildOptionalFields(target?: string, skipVerify?: boolean) {

apps/pair-cli/src/commands/update/handler.test.ts

@@ -206,6 +206,108 @@ describe('handleUpdateCommand - integration with in-memory services', () => {
   })
 })
 
+/**
+ * #186: config override via options.config
+ *
+ * Verifies that handleUpdateCommand uses a custom config when
+ * options.config is provided, and falls back to base config otherwise.
+ */
+describe('#186: config override via options.config', () => {
+  let fs: InMemoryFileSystemService
+  let httpClient: MockHttpClientService
+
+  const cwd = '/project'
+  const datasetSrc = '/project/packages/knowledge-hub/dataset'
+
+  beforeEach(() => {
+    fs = new InMemoryFileSystemService(
+      {
+        [`${cwd}/package.json`]: JSON.stringify({ name: 'test', version: '0.1.0' }),
+        [`${cwd}/packages/knowledge-hub/package.json`]: JSON.stringify({
+          name: '@pair/knowledge-hub',
+        }),
+        [`${cwd}/config.json`]: JSON.stringify({
+          asset_registries: {
+            'test-registry': {
+              source: 'test-registry',
+              behavior: 'mirror',
+              targets: [{ path: '.pair/test-registry', mode: 'canonical' }],
+              description: 'Base registry',
+            },
+          },
+        }),
+        [`${datasetSrc}/test-registry/file.md`]: '# Base Content',
+        [`${datasetSrc}/custom-registry/data.md`]: '# Custom Data',
+        [`${cwd}/.pair/test-registry/file.md`]: '# Old Base',
+      },
+      cwd,
+      cwd,
+    )
+    httpClient = new MockHttpClientService()
+  })
+
+  test('uses custom config registries when options.config is provided', async () => {
+    const customConfig = {
+      asset_registries: {
+        'custom-registry': {
+          source: 'custom-registry',
+          behavior: 'mirror',
+          targets: [{ path: '.pair/custom-target', mode: 'canonical' }],
+          description: 'Custom registry',
+        },
+      },
+    }
+    await fs.writeFile(`${cwd}/custom-config.json`, JSON.stringify(customConfig))
+    // Pre-existing target (update precondition)
+    await fs.mkdir(`${cwd}/.pair/custom-target`, { recursive: true })
+    await fs.writeFile(`${cwd}/.pair/custom-target/data.md`, '# Old Custom')
+
+    const config: UpdateCommandConfig = {
+      command: 'update',
+      resolution: 'default',
+      kb: true,
+      offline: false,
+    }
+
+    await handleUpdateCommand(config, fs, {
+      httpClient,
+      config: `${cwd}/custom-config.json`,
+    })
+
+    expect(await fs.readFile(`${cwd}/.pair/custom-target/data.md`)).toBe('# Custom Data')
+  })
+
+  test('uses base config when options.config is not provided', async () => {
+    const config: UpdateCommandConfig = {
+      command: 'update',
+      resolution: 'default',
+      kb: true,
+      offline: false,
+    }
+
+    await handleUpdateCommand(config, fs, { httpClient })
+
+    expect(await fs.readFile(`${cwd}/.pair/test-registry/file.md`)).toBe('# Base Content')
+  })
+
+  test('throws when options.config points to non-existent file', async () => {
+    // Pre-existing target so we don't fail on the precondition check
+    const config: UpdateCommandConfig = {
+      command: 'update',
+      resolution: 'default',
+      kb: true,
+      offline: false,
+    }
+
+    await expect(
+      handleUpdateCommand(config, fs, {
+        httpClient,
+        config: `${cwd}/nonexistent.json`,
+      }),
+    ).rejects.toThrow(/Failed to load custom config/)
+  })
+})
+
 /**
  * BUG 4: update precondition — targets must exist
  *

apps/pair-cli/src/commands/update/parser.ts

@@ -61,6 +61,7 @@ interface ParseUpdateOptions {
   source?: string
   offline?: boolean
   kb?: boolean
+  config?: string
 }
 
 function resolveSourceConfig(